1 /* 2 * Copyright (C) 2017 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "perfetto/tracing/core/trace_packet.h" 18 19 #include "perfetto/base/logging.h" 20 #include "perfetto/protozero/proto_utils.h" 21 #include "src/tracing/core/sliced_protobuf_input_stream.h" 22 23 namespace perfetto { 24 25 TracePacket::TracePacket() = default; 26 TracePacket::~TracePacket() = default; 27 28 TracePacket::TracePacket(TracePacket&& other) noexcept { 29 *this = std::move(other); 30 } 31 32 TracePacket& TracePacket::operator=(TracePacket&& other) { 33 slices_ = std::move(other.slices_); 34 other.slices_.clear(); 35 size_ = other.size_; 36 other.size_ = 0; 37 return *this; 38 } 39 40 void TracePacket::AddSlice(Slice slice) { 41 size_ += slice.size; 42 slices_.push_back(std::move(slice)); 43 } 44 45 void TracePacket::AddSlice(const void* start, size_t size) { 46 size_ += size; 47 slices_.emplace_back(start, size); 48 } 49 50 std::tuple<char*, size_t> TracePacket::GetProtoPreamble() { 51 using protozero::proto_utils::MakeTagLengthDelimited; 52 using protozero::proto_utils::WriteVarInt; 53 uint8_t* ptr = reinterpret_cast<uint8_t*>(&preamble_[0]); 54 55 constexpr uint8_t tag = MakeTagLengthDelimited(kPacketFieldNumber); 56 static_assert(tag < 0x80, "TracePacket tag should fit in one byte"); 57 *(ptr++) = tag; 58 59 ptr = WriteVarInt(size(), ptr); 60 size_t preamble_size = reinterpret_cast<uintptr_t>(ptr) - 61 reinterpret_cast<uintptr_t>(&preamble_[0]); 62 PERFETTO_DCHECK(preamble_size <= sizeof(preamble_)); 63 return std::make_tuple(&preamble_[0], preamble_size); 64 } 65 66 std::unique_ptr<TracePacket::ZeroCopyInputStream> 67 TracePacket::CreateSlicedInputStream() const { 68 return std::unique_ptr<ZeroCopyInputStream>( 69 new SlicedProtobufInputStream(&slices_)); 70 } 71 72 } // namespace perfetto 73
